The Chesapeake Bay Program announced last week that an estimated 29.6 percent of the Chesapeake Bay and its tidal tributaries met clean water standards for clarity (measured by the abundance of underwater grasses), dissolved oxygen and chlorophyll a (a measure of algae growth) during the 2018-2020 assessment period.

This is lower than the previous score of 33.1 percent received during 2017-2019. However, while the water quality of the Chesapeake Bay and its tidal tributaries saw a decrease of 3.5 percent from the previous assessment period, the U.S. Geological Survey reported mixed results in the trends of nitrogen, phosphorus and sediment pollution entering the bay from the largest rivers in the watershed, a release stated.

Further analysis of tidal water results reveals some improvement of the Chesapeake’s water quality. Despite record high river flows to the Chesapeake in 2019, dissolved oxygen levels in the deep waters saw significant improvement in their attainment of crite...